DEPARTMENT OF GENETICS. 129 



of the factor of heredity in the behavior of dogs. This study is being 

 conducted by Dr. E. C. MacDowell. He reports progress as follows: 



In attempting to discover the laws controlling the inheritance of a tendency 

 to specific behavior by following the course of such tendency through crosses 

 and successive generations, the first and most difficult problem is to find suita- 

 ble methods of recognizing the specific behavior when manifest. Once such 

 methods are formulated, the work can proceed with certainty to a successful 

 conclusion, however long and tedious may be the road. In discovering 

 suitable methods distinct progress has been made at this Station, The first 

 apparatus designed to measure the behavior and educability of dogs has been 

 in operation since the beginning of the year. Its main object has been to 

 provide a simple method of testing the responsiveness of different individuals, 

 and, more especially, different breeds, to various types of signals. So far the 

 work has been restricted to one breed of dogs, namel}^, dachshunds. Instead 

 of learning to follow a certain path, the dogs were given the problem of learning 

 to choose between alternative paths according to signals, that is, to form the 

 association between a certain signal and their food. An important feature 

 of the apparatus (see figure 3) is the arrangement which permits the dogs to 

 leave their kennels and go through 10 or more trials a day without seeing the 

 observer. The observer remains in the closet 0, where the records are made 

 and from which all doors and signals are operated. By means of mirrors, 

 electric signals, peep-holes, and the sounds made by the dogs themselves, the 

 course of the animals can be followed. The kennels are provided with sliding 

 doors which are opened by long cords. Released from his kennel, the dog 

 to be trained passes over the gangway to the house through the opened door 

 F, which is closed behind him, on to door M, which is also open. When he 

 reaches the end of the central alley the signal is given at the right or left side 

 of the house. If the association has been formed the dog will turn towards 

 the signal and continue around to the side alley (doors PI and Pr always being 

 open); by stepping on the board L or 72 a light signal is given in for the 

 observer to open the next door {Sl or Sr) into the food compartment. Door S 

 is immediately lowered again, a morsel of food dropped into the food com- 

 partment by a device operated from 0, and, after eating, the dog leaves this 

 compartment by door E and thence to M and through the apparatus again. 

 This is continued until the desired number of trials has been run (10 per day), 

 when the dog finds M closed and leaves the house. If a wrong choice is made 

 in the trials, that is, if a dog turns away from the signal, the door S on that 

 side will not be opened and the dog must correct himself by going to the 

 opposite side. In order to prove that a real association, and not merely a 

 rhythm, has been formed, the signals are given on one side or the other accord- 

 ing to the order of the red and black spots in two well-shuffied packs of playing 

 cards. It is obvious that half the choices will be correct by chance even if no 

 association at all is formed. The long series of daily trials is given to obtain a 

 more reliable measure of the proportion of correct choices. 



The first signals used were electric lights, located at the ends of the trans- 

 verse alley, visible when the dog reached the end of the central alley. Although 

 the house was not completely dark, the transverse alley was sufficiently in 

 shadow to make a great contrast between the illuminated end and the opposite 

 one. The first litter to be trained in this apparatus included 5 one-year-old 

 dachshunds (ex Cocoa by Engadin); they adjusted themselves immediately 

 to the routine of the apparatus. The mother. Cocoa, was trained at the same 

 time and showed the same adaptability to the apparatus. Some of these 

 learned to return to their kennels when they found door M closed after their 



